1. Technical Field
The present invention relates generally to robotics and more specifically to telepresence systems.
2. Background Art
In the past, video camera and audio systems were developed for improving communication among individuals who are separated by distance and/or time. The systems and the process are now referred to as “videoconferencing”. Videoconferencing sought to duplicate, to the maximum extent possible, the full range, level and intensity of interpersonal communication and information sharing which would occur if all the participants of a meeting were “face-to-face” in the same room at the same time.
In addition to spoken words, demonstrative gestures, and behavioral cues, face-to-face contact often involves sitting down, standing up, and moving around to look at objects or people. This combination of spoken words, gestures, visual cues, and physical movement significantly enhances the effectiveness of communication in a variety of contexts, such as “brainstorming” sessions among professionals in a particular field, consultations between one or more experts and one or more clients, sensitive business or political negotiations, and the like.
Behavioral scientists know that interpersonal communication involves a large number of subtle and complex visual cues, referred to by names like “gaze” and “eye contact,” which provide additional information over and above the spoken words and explicit gestures. Gaze relates to others being able to see where a person is looking and eye contact relates to the gazes of two persons being directed at the eyes of the other. These cues are, for the most part, processed subconsciously by the people, and often communicate vital information.
In situations where all the people cannot be in the same place at the same time, the beneficial effects of face-to-face contact will be realized only to the extent that a remotely located person, or “user”, can be “recreated” at the site of the meeting where the “participants” are present.
In robotic telepresence, a remotely controlled robot simulates the presence of the user. The overall experience for the user and the participants interacting with the robotic telepresence device is similar to videoconferencing, except that the user has a freedom of motion and control over the robot and video input that is not present in traditional videoconferencing. The robot platform typically includes a camera, a display device, a motorized platform that includes batteries, a control computer, and a wireless computer network connection. An image of the user is captured by a camera at the user's location and displayed on the robotic telepresence device's display at the meeting.
In video communication systems where moveable or zoomable video cameras at a remote location are under control of a local user, feedback delays can cause difficulties for users in adjusting to camera motion at the remote location. This motion may be of several types. As is present in many commercial video conferencing systems, a camera at the remote location could be panned, tilted, or zoomed by a person viewing the video remotely.
In other systems, the XY location of the camera may change with motion of the camera platform i.e., translation. A typical example of this is that the user may direct the camera to point to an object to the right of their current viewpoint. They may stop requesting the camera to move when they see the desired object centered on their video screen.
However, additional delays in the control loop can cause the actual position of the camera to overshoot the desired position of the camera. Sources of delays include: transmitting commands to the remote camera, the motion of the camera based on those commands, acquisition of video imagery, compression of the video, transmission of the video, decompression of the video, and rendering the video on a display device.
As more complex systems evolve, control of the remote positioning can become even more complex. The user navigates through a remote environment based on this video feedback. However, delays of several seconds can occur between user commands such as controlling speed via a pistol grip and the resulting change in video presentation for the user.